Often, PCB design guidelines are overlooked, and more attention is given to circuit design, functionality, and component selection. However, failing to consider the basics of PCB layout can result in a design that is challenging to fabricate and does not translate well from the digital domain to the physical realm. To improve manufacturability, functionality, and reliability, we recommend following the top five PCB design guidelines:
- Carefully Place Components Component placement is a critical step that determines how easily the board can be manufactured and how well it meets design requirements. When placing electronic components, consider the available PCB real estate on your board. There are various PCB layout rules to follow during component placement, such as orienting similar components in the same direction to facilitate effective routing and efficient soldering.
- Route Power, Ground & Signal Traces After placing components, route power, ground, and signal traces to ensure a clean and trouble-free path of travel for signals. Keep in mind that it’s best to place power and ground planes internal to the board, keeping them symmetrical and centered, and to keep traces as short and direct as possible between components. The design rules and guidelines become more complex as the number of layers in your stack-up increases, and your routing strategy will require alternating horizontal and vertical traces in alternating layers.
- Keep Things Separate Separate power ground and control ground for each power supply stage to avoid interference issues. If you have placed your ground plane in the middle layer, be sure to place a small impedance path to reduce the risk of any power circuit interference and to help protect your control signals. To reduce capacitive coupling, have your analog ground crossed only by analog lines.
- Minimize Heating Issues Identify components that will dissipate the most heat on your board and follow the recommended guidelines to divert the heat being produced. Distribute these components throughout the board instead of clustering them in one location. Use thermal reliefs on through-hole components to slow the rate of heat sinking through the component plates and consider adding teardrops where traces join pads to reduce mechanical and thermal stress.
- Verify Your Layout Against PCB Design Rules Double-check your work for any errors and run your Electrical Rules Check (ERC) and Design Rules Check (DRC) to ensure you’ve met all of your established constraints. Consider running these checks throughout the design process to identify potential problems early and correct them quickly.